Calcium is essential for building and maintaining bone strength, nerve transmission to the muscles, serving as a catalyst for the conversion of prothrombin to thrombin and activating a number of enzymes including lipase. Calcium deficiency can lead to osteoporosis in the elderly. Additionally, protection against high blood pressure and colon cancer have been attributed to calcium. The U.S. Recommended Daily Allowance, commonly referred to as the Reference Daily Intake (“RDI”), of calcium is 1000 mg for adults and children 12 or more years of age.
Calcium and other minerals and vitamins have been used to fortify foods to obtain general health benefits. To get enough calcium for growing bones, the percent Daily Value for calcium should add up to 120 percent. Foods fortified with calcium are considered to offer the same net effect as calcium naturally found in food.
Dairy products are recognized as a rich source of dietary calcium. Both milk and ice cream have been fortified with calcium. Calcium fortification of milk is disclosed in U.S. Pat. Nos. 2,871,123, 4,701,329, 4,840,814 and 4,851,243; see also Anon, Boosting Milk's Calcium, 99 Dairy Foods 36, 1998. For example, milk has been fortified with calcium carbonate, calcium gluconate and milk calcium in powdered form.
U.S. Pat. No. 5,002,779 to Mehansho describes addition of calcium to dry chocolate powers such as cocoa. Carrageenan gum has been used for suspension of calcium carbonate. U.S. Pat. Nos. 4,701,329 and 4,851,243 disclose calcium-enriched and phosphorus-enriched fortified milk by the addition of tri-basic calcium phosphate, carrageenan and guar gum to milk. The hydration of the gums is necessary to assure uniform distribution of the added materials in the milk.
However, there are many obstacles associated with adding calcium to syrups that make it very difficult to utilize. For example, when added directly to syrup as a salt without being subjected to any further treatment, many of the calcium salts, which are insoluble or substantially insoluble at around neutral pH, e.g., calcium carbonate, calcium phosphates, calcium citrate and other organic or inorganic acid salts of calcium, precipitate out of the syrup or impart to the syrup a gritty chalky mouthfeel. Fortification with calcium is a significant challenge, especially in foods, such as syrups, which are ingested in small serving sizes. Syrups are packaged in standard 24 ounce bottles which include approximately 16 servings per bottle. The smaller serving size and the higher number of servings in a container for syrups is a problem since a high concentration of calcium is necessary in the small volume if it is being used to fortify this food. Also problematic is the availability of calcium from various salt ingredients. Typically, the amount of calcium in various salt forms only ranges from 20-40% based on the source.
An additional problem with calcium fortification is that most calcium sources, such as calcium carbonate, have a very poor solubility in water or in neutral pH solutions. Calcium that is very soluble in orange juice, for example, will not be soluble in chocolate syrup. Syrups are typically low water mixtures, that is, there is not a lot of available water. This poor solubility coupled with low water availability in syrups prevents calcium from becoming soluble in the system. When incorporating calcium into liquids, the source of calcium is usually in finely divided form which further promotes precipitation thereof upon extended storage.
Syrups are products which typically are expected to have much longer shelf lives than products such as milk or yogurt. The addition of untreated calcium salts to syrups causes the syrup to have a gritty texture; moreover sedimentation of calcium on the bottom of the container is likely to occur during processing and/or shelf life. More soluble calcium salts or even the use of suspended sources of calcium tends to result in off flavors, adverse appearance, and undesirable increases in viscosity. Generally, the more soluble the salt or the more finely divided it is so as to improve supendability, the quicker or more easily the off-taste will be detected. Also, solubilization of the calcium increases the likelihood of it being complexed with or interacting with other components of the syrup or other foods consumed with it. Additionally, complexation or interaction of the calcium may result in it being less susceptible to absorption in the blood.
Therefore, there is a need for a calcium fortified syrup which is flavor neutral and not unpleasant tasting or gritty and from which the calcium does not separate out.